Quarterly report pursuant to Section 13 or 15(d)

SECURITIES (Details)

v2.4.1.9
SECURITIES (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2014
Available for Sale [Abstract]      
Amortized Cost $ 154,348us-gaap_AvailableForSaleSecuritiesAmortizedCost   $ 161,781us-gaap_AvailableForSaleSecuritiesAmortizedCost
Gross Unrealized Gains 1,449us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax   926us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Gross Unrealized Losses (157)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax   (833)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Fair Value 155,640us-gaap_AvailableForSaleSecurities   161,874us-gaap_AvailableForSaleSecurities
Proceeds from sale of available-for-sale securities 12,063us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities 561us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities  
Gain on sale of securities 83us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNet 10us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNet  
Reclassification adjustment for securities gain recognized in earnings, net of tax 54us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax 7us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax  
Held to Maturity [Abstract]      
Amortized Cost 43,042us-gaap_HeldToMaturitySecurities   31,585us-gaap_HeldToMaturitySecurities
Fair Value 43,402us-gaap_HeldToMaturitySecuritiesFairValue   31,428us-gaap_HeldToMaturitySecuritiesFairValue
Tax-Exempt State and Municipal Bonds [Member]      
Held to Maturity [Abstract]      
Amortized Cost 43,042us-gaap_HeldToMaturitySecurities
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
  31,585us-gaap_HeldToMaturitySecurities
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
Gross Unrealized Gains 372us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
  64us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
Gross Unrealized Losses (12)us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
  (221)us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
Fair Value 43,402us-gaap_HeldToMaturitySecuritiesFairValue
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
  31,428us-gaap_HeldToMaturitySecuritiesFairValue
/ us-gaap_DebtSecurityAxis
= us-gaap_NontaxableMunicipalBondsMember
U.S. Treasury and Federal Agency Securities [Member]      
Available for Sale [Abstract]      
Amortized Cost 65,619us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
  67,612us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
Gross Unrealized Gains 162us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
  53us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
Gross Unrealized Losses (81)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
  (501)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
Fair Value 65,700us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
  67,164us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USTreasuryAndGovernmentMember
U.S. Agency MBS and CMOs [Member]      
Available for Sale [Abstract]      
Amortized Cost 15,832us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
  16,692us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Gross Unrealized Gains 114us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
  67us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Gross Unrealized Losses (14)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
  (71)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Fair Value 15,932us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
  16,688us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Tax-Exempt State and Municipal Bonds [Member]      
Available for Sale [Abstract]      
Amortized Cost 35,643us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
  37,203us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
Gross Unrealized Gains 637us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
  419us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
Gross Unrealized Losses (53)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
  (161)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
Fair Value 36,227us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
  37,461us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_NontaxableMunicipalBondsMember
Taxable State and Municipal Bonds [Member]      
Available for Sale [Abstract]      
Amortized Cost 23,520us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
  25,012us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
Gross Unrealized Gains 446us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
  351us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
Gross Unrealized Losses (6)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
  (70)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
Fair Value 23,960us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
  25,293us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TaxableMunicipalBondsMember
Corporate Bonds and Other Debt Securities [Member]      
Available for Sale [Abstract]      
Amortized Cost 12,234us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
  13,762us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
Gross Unrealized Gains 74us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
  34us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
Gross Unrealized Losses (3)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
  (30)us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
Fair Value 12,305us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
  13,766us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_CorporateBondsAndOtherDebtSecuritiesMember
Other Equity Securities [Member]      
Available for Sale [Abstract]      
Amortized Cost 1,500us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember
  1,500us-gaap_AvailableForSaleSecuritiesAmortizedCost
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember
Gross Unrealized Gains 16us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember
  2us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember
Gross Unrealized Losses 0us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember
  0us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember
Fair Value $ 1,516us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember
  $ 1,502us-gaap_AvailableForSaleSecurities
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= mcbc_OtherEquitySecuritiesMember